per-object-permissions: Merged to trunk [5486] NOTE: Not fully tested, will be working on this over the next few weeks.

git-svn-id: http://code.djangoproject.com/svn/django/branches/per-object-permissions@5488 bcc190cf-cafb-0310-a4f2-bffc1f526a37

2 files changed, 101 insertions, 4 deletions

diff --git a/django/db/backends/postgresql_psycopg2/base.py b/django/db/backends/postgresql_psycopg2/base.py
index 04322332dc..d9ad363ac1 100644
--- a/django/db/backends/postgresql_psycopg2/base.py
+++ b/django/db/backends/postgresql_psycopg2/base.py
@@ -12,6 +12,7 @@ except ImportError, e:
     raise ImproperlyConfigured, "Error loading psycopg2 module: %s" % e
 
 DatabaseError = Database.DatabaseError
+IntegrityError = Database.IntegrityError
 
 try:
     # Only exists in Python 2.4+
@@ -20,6 +21,8 @@ except ImportError:
     # Import copy of _thread_local.py from Python 2.4
     from django.utils._threading_local import local
 
+postgres_version = None
+
 class DatabaseWrapper(local):
     def __init__(self, **kwargs):
         self.connection = None
@@ -28,7 +31,9 @@ class DatabaseWrapper(local):
 
     def cursor(self):
         from django.conf import settings
+        set_tz = False
         if self.connection is None:
+            set_tz = True
             if settings.DATABASE_NAME == '':
                 from django.core.exceptions import ImproperlyConfigured
                 raise ImproperlyConfigured, "You need to specify DATABASE_NAME in your Django settings file."
@@ -45,16 +50,22 @@ class DatabaseWrapper(local):
             self.connection.set_isolation_level(1) # make transactions transparent to all cursors
         cursor = self.connection.cursor()
         cursor.tzinfo_factory = None
-        cursor.execute("SET TIME ZONE %s", [settings.TIME_ZONE])
+        if set_tz:
+            cursor.execute("SET TIME ZONE %s", [settings.TIME_ZONE])
+        global postgres_version
+        if not postgres_version:
+            cursor.execute("SELECT version()")
+            postgres_version = [int(val) for val in cursor.fetchone()[0].split()[1].split('.')]        
         if settings.DEBUG:
             return util.CursorDebugWrapper(cursor, self)
         return cursor
 
     def _commit(self):
-        return self.connection.commit()
+        if self.connection is not None:
+            return self.connection.commit()
 
     def _rollback(self):
-        if self.connection:
+        if self.connection is not None:
             return self.connection.rollback()
 
     def close(self):
@@ -96,6 +107,9 @@ def get_limit_offset_sql(limit, offset=None):
 def get_random_function_sql():
     return "RANDOM()"
 
+def get_deferrable_sql():
+    return " DEFERRABLE INITIALLY DEFERRED"
+
 def get_fulltext_search_sql(field_name):
     raise NotImplementedError
 
@@ -105,6 +119,88 @@ def get_drop_foreignkey_sql():
 def get_pk_default_value():
     return "DEFAULT"
 
+def get_sql_flush(style, tables, sequences):
+    """Return a list of SQL statements required to remove all data from
+    all tables in the database (without actually removing the tables
+    themselves) and put the database in an empty 'initial' state
+    """
+    if tables:
+        if postgres_version[0] >= 8 and postgres_version[1] >= 1:
+            # Postgres 8.1+ can do 'TRUNCATE x, y, z...;'. In fact, it *has to* in order to be able to
+            # truncate tables referenced by a foreign key in any other table. The result is a
+            # single SQL TRUNCATE statement
+            sql = ['%s %s;' % \
+                    (style.SQL_KEYWORD('TRUNCATE'),
+                     style.SQL_FIELD(', '.join([quote_name(table) for table in tables]))
+                    )]
+        else:
+            sql = ['%s %s %s;' % \
+                    (style.SQL_KEYWORD('DELETE'),
+                     style.SQL_KEYWORD('FROM'),
+                     style.SQL_FIELD(quote_name(table))
+                     ) for table in tables]
+                     
+        # 'ALTER SEQUENCE sequence_name RESTART WITH 1;'... style SQL statements
+        # to reset sequence indices
+        for sequence in sequences:
+            table_name = sequence['table']
+            column_name = sequence['column']
+            if column_name and len(column_name) > 0:
+                # sequence name in this case will be <table>_<column>_seq
+                sql.append("%s %s %s %s %s %s;" % \
+                    (style.SQL_KEYWORD('ALTER'),
+                     style.SQL_KEYWORD('SEQUENCE'),
+                     style.SQL_FIELD(quote_name('%s_%s_seq' % (table_name, column_name))),
+                     style.SQL_KEYWORD('RESTART'),
+                     style.SQL_KEYWORD('WITH'),
+                     style.SQL_FIELD('1')
+                     )
+                )
+            else:
+                # sequence name in this case will be <table>_id_seq
+                sql.append("%s %s %s %s %s %s;" % \
+                    (style.SQL_KEYWORD('ALTER'),
+                     style.SQL_KEYWORD('SEQUENCE'),
+                     style.SQL_FIELD(quote_name('%s_id_seq' % table_name)),
+                     style.SQL_KEYWORD('RESTART'),
+                     style.SQL_KEYWORD('WITH'),
+                     style.SQL_FIELD('1')
+                     )
+                )
+        return sql
+    else:
+        return []
+
+def get_sql_sequence_reset(style, model_list):
+    "Returns a list of the SQL statements to reset sequences for the given models."
+    from django.db import models
+    output = []
+    for model in model_list:
+        # Use `coalesce` to set the sequence for each model to the max pk value if there are records,
+        # or 1 if there are none. Set the `is_called` property (the third argument to `setval`) to true
+        # if there are records (as the max pk value is already in use), otherwise set it to false.
+        for f in model._meta.fields:
+            if isinstance(f, models.AutoField):
+                output.append("%s setval('%s', coalesce(max(%s), 1), max(%s) %s null) %s %s;" % \
+                    (style.SQL_KEYWORD('SELECT'),
+                    style.SQL_FIELD(quote_name('%s_%s_seq' % (model._meta.db_table, f.column))),
+                    style.SQL_FIELD(quote_name(f.column)),
+                    style.SQL_FIELD(quote_name(f.column)),
+                    style.SQL_KEYWORD('IS NOT'),
+                    style.SQL_KEYWORD('FROM'),
+                    style.SQL_TABLE(quote_name(model._meta.db_table))))
+                break # Only one AutoField is allowed per model, so don't bother continuing.
+        for f in model._meta.many_to_many:
+            output.append("%s setval('%s', coalesce(max(%s), 1), max(%s) %s null) %s %s;" % \
+                (style.SQL_KEYWORD('SELECT'),
+                style.SQL_FIELD(quote_name('%s_id_seq' % f.m2m_db_table())),
+                style.SQL_FIELD(quote_name('id')),
+                style.SQL_FIELD(quote_name('id')),
+                style.SQL_KEYWORD('IS NOT'),
+                style.SQL_KEYWORD('FROM'),
+                style.SQL_TABLE(f.m2m_db_table())))
+    return output
+        
 OPERATOR_MAPPING = {
     'exact': '= %s',
     'iexact': 'ILIKE %s',
diff --git a/django/db/backends/postgresql_psycopg2/introspection.py b/django/db/backends/postgresql_psycopg2/introspection.py
index a546da8c45..aa45fe7db7 100644
--- a/django/db/backends/postgresql_psycopg2/introspection.py
+++ b/django/db/backends/postgresql_psycopg2/introspection.py
@@ -72,6 +72,7 @@ DATA_TYPES_REVERSE = {
     21: 'SmallIntegerField',
     23: 'IntegerField',
     25: 'TextField',
+    701: 'FloatField',
     869: 'IPAddressField',
     1043: 'CharField',
     1082: 'DateField',
@@ -79,5 +80,5 @@ DATA_TYPES_REVERSE = {
     1114: 'DateTimeField',
     1184: 'DateTimeField',
     1266: 'TimeField',
-    1700: 'FloatField',
+    1700: 'DecimalField',
 }